Envelope sealing machine



Sept. 9, 1952 w, H|

ENVELOPE SEALING MACHINE l0 Sheets-Sheet 3 Filed Marph 18, 1949 MFi n NI mm b Q m 5 HUM ATTORNEYS Sept. 9, 1952 Filed March 18 1949 w. H. UHL

ENVELOPE SEALING MACHINE 10 Sheets-Sheet 4 INVENTOR William/H ZJ/zl ATTORNEYS p 1952 w. H. UHL 2,609,790

ENVELOPE SEALING MACHINE Filed March 18, 1949 10 Sheets-Sheet 5 i- 592 ZQ 98 1:; PE E].

64b 82 64a 94 g 464 88 liinTxw 84 INVENTOR Wz'ZZzamIiZJM 2/4 @Qm 8M 2061) ATTORNEYS Sept. 9, 1952 w, L

ENVELOPE SEALING MACHINE l0 Sheets-Sheet 7 Filed March 18, 1949 %,Q& ATTORNEYS uwEN'roR Wailzamjidh Sept. 9, 1952 w UHL 2,609,790

ENVELOPE SEALING MACHINE Filed March 18, 1949 lo Sheets-Sheet 8 INVENTOR ATTORNEYS Sept. 9, 1952 w. H. UHL

ENVELOPE SEALING MACHINE l0 Sheets-Sheet 9 Filed Margh 18, 1949 1 ATTORNEYS Sept. 9, 1952 w. H. UHL

ENVELOPE SEALING MACHINE l0 Sheets-Sheet 10 Filed March 18, 1949 INVENTOR mummy. lJ/zl midi ATTORNEYS .thewater tank shown inFigure 3;

Patented Sept. 9, 1952 UNITED STATES PATENT: O FI ENVELOPE tmcnnvii M William H. Uhl, Rochester, Y., assigiior to Commercial Controls Corporation, Rochester,

Application March 18, 1949, Serial No. 82,037

11 Claims.

This invention relates to a letter sealing machine.

One of the objects of this invention is to provide a new and improved letter sealing machine. Another object is to provide amachine of theabove character which isefficient anddependablein operation, simple and sturdy in construction, and relatively inexpensive to build, operate andmaintain. Another object is to provide a machine of the above character which is able to seal a maximum of letters in a minimum of time. A further object is to provide a machine of the above character, in which the moistening of the flap of each envelope passing throughthe machine is assured A still further object is to provide a machine of the above character which will emciently seal envelopes of a large number of different thicknesses and sizes. Other objects will'be in part obvious and in part pointed out hereinafter.

The invention accordingly consists in the features of construction, combinations of elements, and arrangements of parts, all as will be illustratively described herein and thescope of the application of which will be indicated, in the following claims.

p In: the accompanying drawings, in which is shownone of the various possible embodiments of thisinvention:

Figure 1 is a perspective view of a complete machine; l

Figure 2 is a top plan view of the machine, certain parts being removed for purposes of illustration;

Figure 3 is a front elevation of the machine, certain parts of the housing being removed and other parts shown in section for purposes of illustration;

Figure 4 is a'horizontal section taken on the line 4-4 of Figure 3;

(Child-401) Figure 13 is a vertical section taken on the line 13-13 of Figure 11;

Figure 14 is a'vertical section taken on the line |4--M of Figure 2;

Figure 15 is a perspective view of the sealer table;

Figure 16 is a perspective viewof one of the pressure feet shown in Figure 14; f Iligure 17 is a perspective view of the separator Figure 18 is a plan of another pressure foot;

Figure 18a is a side elevation of the pressure foot, shown in Figure 18, Figure 19 isa rear view of the sealer table shown in Figure 15 when detached from the machine; v

Figure 20 is a bottom plan of the sealer table shown in Figures 15 and 19;

Figure 21 is a1 vertical section taken on the 0 line 2 |-2l of Figure 20;

Figure 5 is a staggered vertical section taken on the line 5-5 of Figure 3;

Figure 6 is a horizontal section on an enlarged scale taken on the line 6-6 of Figure 3; certain parts being broken away for purposes of illus- 5 tration;

Figure 7 is a top plan on an enlarged scale 01' Figure 8 is a staggered vertical section taken through the water Figure 7;

Figure 9 is a staggered vertical section showing the upper portion of the water tank taken on the line 9- -9 of Figure 7;

Figure 10 is a staggered vertical section taken on the line Ill-I0 of Figure 7;

Figure 11 is a staggered vertical section taken onthe line Illl of Figure 2;

Figure 12 isa staggered vertical section taken on the line l2--I2 of Figure 11;

tank on the line 8-8 of 5 Figure 22 is a vertical section taken on the line 22-22 ofFigure 20;

Figure 23 is a vertical section taken on the line 2 3-23 of Figure 21;

Figure 24 is a horizontal section taken on the line 24-44 of Figure 21; and,

Figure 25 is a staggered horizontal section taken on the line 25-25 of Figure 21.

Similar reference characters refer to similar parts throughout the several views of the drawmgs.

In general, the machine includes a motor 30 (Figures 3 and 4), which drives a conveyor belt 32 and feed roller 34 through pulley and belt assemblies to be described hereinafter. Motor 30 also actuates a diaphragm pump, generally indicated at 36 (Figures 3 and '4), mounted on a tank, generally indicated at 38. Diaphragm pump 36 (Figure 3) pumps water upwardly to the sealer blade assembly, generally indicated at 40 (Figures 19 and 20) mounted on sealer table 42 and continuously circulates water through the sealer blade. This prevents the 'sealer blade from becoming clogged by adhesive or other foreign material, all as will be clearly pointed out hereinafter. The supply of envelopes to be sealed is supported by the hopper table 44and the guide lfi (Figures 1 and 2). removed from the stack positioned above hopper table 44 by conveyor belt 32 one at a time. Con

Envelopes are pulley it through a belt 88.

of the rear portion on the machine is covered by a sheet metal cover E2 (Figure 1), and the front of rear portion 12 is covered by a vertically posi tioned plate M.

The base of motor 38 is secured to bottom 58 (Figures 3 and 4) and it has a pulley 18 mounted on and secured to its drive shaft, which drives Pulley 18 (Figure 4-) is mounted on and secured to the rear end of shaft 82 (Figure 6), which is rotatably mounted in a bearing member 64a formed on center wall 84. On the forward side of wall 64 (Figures 4 and 6), a pair of pulleys 8 3 and 86 are mounted on and connected to shaft 82. To mount pulleys 84 and onshaft 82, shaft 82 is provided with an enlarged portion 88, against which the hub portions of pulleys 84 and 86am clamped by means of a hex nut 98.

As'described above, the envelopes are fed from hopper table 44 across the sealer table 62 by means of conveyor belt 32. driven by pulley 85 (Figures 3, 4 and 6), and its left-hand end, as viewed in Figure 3, is supported by pulley 92. The hub82a of pulley 82 ispinned to a shaft 96 by a taper'pin 85d Shaft 94 is rotatably mounted on a bearing member fi ib' formed as an integral part of wall 'fi i. Shaft 94 is prevented from moving rearwardly by means of a shoulder Sea formed on shaft 84, and is prevented from moving forwardly by means of collar 88 pinned to shaft 9 3. Thus, as the motor drives pulley 85, it drives pulley. 92- through belt 52. Thus, belt 32 (Figure 3) is driven by pulley 85 and is supportedin envelope-feeding position by means of pulley 82. The upper portion of the'belt, as viewed in Figures 2 and 3, is positioned beneath separator foot 58 and pressure feet 58 and 52, with which it coacts to feed the envelopes across sealer table 42.

Referring to Figure 5, the forward end of shaft 84 has a threaded hole )8 therein. This hole is aligned with a bearing I82 (Figures 3, 4 and 5) m'ounted'on a bracket lM. Bracket I84 is secured to a supporting'bar I85 (Figures 3,4 and 5), whichis secured to end walls 88 and 62 by screws Hi8 and IIil (Figure 3). .Bearing I82 (Figure 1) extends through cover 88 and is adapted to receive the shank of a crank (not shown), the inner end of which threads into hole I88 (Figuresa and 6) inshaft 98. Thus, pulley 92 may be manuallydriven by a crank and the emainder of the mechanism of the sealing machine driven through belt 32.

- To drive feed roller 34, pulley 84 (Figuresl, 5 ands) is connected to-a pulley S laformed on the hub of feed roller 3% by a belt H2. One end of feed roller shaft IM (Figures 3, l and 5) is rotatably mounted on a bearing He (Figure 4) mounted on a bracket H8 (Figures :3 and 4) formed on end wall 65. The other end of shaft H 3 is rotatably mounted on a bearing mounted on centerawall E i.

As best shown in Figures 11 and 15, the end of sealer table 42 has a cutout portion 522 therein to permit feed roller 3 to engage the undersurface of envelopes leaving the sealer table.

Conveyor belt 32 is The envelopes are pressed into contact with feed roller 34 by pressure roller 56 (Figures 3, 5 and 11); Pressure roller 58 has stud shafts-55a and 56b (Figure 5) thereon, which rotatably mount roller 58 on the sides I26a and I255 of a support I26 (Figures 3, 5 and 11). Support 126 (Figure 2) is pivotally mounted on the forward end of a stud shaftIZS by means of a pair of rightangle brackets l32-and I34 (Figures 2 and 3) secured to the top surface of support I26. The rear portion of'shaft I28 has a section I28a of reduced diameter, which extends through center wall 6 Shaft I28 is secured to wall 64 by means of nut I35. The forward portion [28b of shaft I28 is also of a reduced diameter to form a seat I280 between the forward portion of shaft I28 and its center section. The forward portion I281) of shaft I28 extends through aligned holes in the spaced upwardly-extending portions of brackets I32 and I34.

To hold support I 28 properly aligned with respect to feed roller 3:1 and to resiliently press pressure'roller 58into contact with feed roller 34, a coil spring H6 is mounted on the outer end of portion I282) of support I28. This spring is maintained under compression longitudinally of its axis by means of a nut I38 mounted on the outer end of support I28. Thus, spring I36 resiliently presses against bracket I82 and holds bracket !34 in engagement with seat I280. Spring I38 is also under coaxial tension, having one end anchored on nut1l38 and the other end l35a (Figures 2 and ,3) bearing downwardly upon the upper surface of support 25; This force resiliently holds roller 55' in engagement with feed roller 35 (Figures 5 and 11) Referring to Figure 11,"it will bepnoted that roller 34 has a rubber sleeve 34b mounted thereon, forming. its feeding surface; This resilient sur- 7 face of roller 34 coacts with the corrugations 56c (Figure 5) formed on'the surface ofzpressure roller 58 toensure feeding the'envelopes without slippage, and also concentrates thelpressure'of pressure roller 56 to ensure complete sealing of each envelope. Thus, feeding and pressure rollers 34 and 56, when driven by belt H2 (Figures 4 and5), feed envelopes from the machine as they are fed to them by conveyor belt 32, and at the same time, seal each envelope in an-e fiicient and practical manner. v I

As pointed out hereinabove, the sealer blade assembly 48 (Figure 20)}which is mounted on the undersurface of sealer table 42 and which moistens the gummed surface of the envelope flaps, is continuously supplied with a flow of water from tank 38 (Figure 3) when the machine is in operation. Tank38 is made from aplastic material asa unit and includes integral sidewalls 38a and 38b (Figures 3 and 8), end walls 380 and 38d, and a bottom 88a. The tank is provided with feet I48 (Figures 3 and 8) to support it above the bottom 58 ofthe frame of the machine, and at its right-hand end (Figure 8) has a removable screen M2'mounted in a slot I44 in a supporting rib M8 which extends down sides 38a and 88b (Figures 3 and 8) and across the bottom 38c of tank 38. Screen I42 divides the tank 38 into overflow and supply sections I88 and I58 for purposes to be more fully. disclosed hereinafter. I

The top of tank 38 isclosedby a cover, gen

erally indicated at 52 (Figures 3, 4, '7 andjB). The edge of cover E52 is provided with ;a gasket seat (Figure 8) for a gasket I55. Cover I52 (Figure 3) is held on tank 38 and tank's}; is held in position on the machine by a pair of hook shaped clamps I58 and I60. The lower endsofclamps I58 and I60 are threaded and extend through holes in the bottom 58 of the frame of themachine. Wing nuts I62 and I64 are provided to draw clamps I58 and I60 into clamping relationship with respect to cover I52, and thus tank 38. When clamps I58 and I60 are tightened, gasket I56 (FigureS) engages aflange 38 extending outwardly from the upper edge of the tank andthus seals the joint between cover I52 and tank 38. l

To fill tank 38, it is provided with an opening I65 (Figure 9) in cover I52, which is closed by a removable plug I66 (Figures 4 and 9). When it is desired to fill tank 38, housing cover 68 (Figures Land 4) is removed, permitting ready access .to opening I65, which is positioned adjacent the front of the machine. To permit air to enter the tank as water is removed from it, cover I52 is provided with a'dome I52b (Figures 4 and 8) which has an opening I53 in the upper portion thereof. 1

Water is pumped to the sealer bladeassembly by diaphragm pump 36. The casing, generally indicated at I68 (Figures 8 and of the pump is formed as an integral part'of the tank cover I52. The casing includes a well portion I 68a which has a cylindrically-shaped Wall and a bottom. Extending downwardly from well portion I 68a is an intake duct I68b, the lower end of which is positioned adjacent the bottom 386 of tank 38. A ball I12 coacts with a seat I18 formed in the lower end of intake duct 5% to form the intake valve for the pump. .To limit the upward movement of ball I12 during the intake stroke of the pump, a flat wedge I14 is wedged tightly into intakeduct I'68b from the upper end thereof.

. During periods of extended usage, it is possible forforeign matter to collect in the supply section of the tank from which the diaphragm pump draws water. This foreign matter can enter intake duct H581), and if the tank then dries because of non use, ball I12 may stick to seat I10. To provide ready means for freeing ball I12, a freeing wire, generally indicated at I16, is provided. This wire includes a U-shaped bottom portion I16a, one end of which is positioned in the lower end of duct I68b. Wire I16 extends upwardly through the cover of the tank to provide a portion I16b readily accessible to the operator of the pump. Thus, if the pump fails to pump, the operator raises the freeing wire I16 byportion I161). The portion of wire I16 positioned in duct [681) then engages ball I12 and frees it from seat I10. As wire I16 is freely mounted in the hole through the cover and portions of the diaphragm pump, gravity at all times keeps it in an inoperative position except when it is being used to free ball I12. 1

. The well I68a of pump 36 is provided with an exhaust duct I680 which extends downwardly from the pump to permit a plastic conduit I 18 to be. connected to it. .Conduit I18;connects exhaust duct I680 to a checkvalve, generally indicated at I80, on cover I52 (Figure 9) The body of valve I80 is formed as an integral part of cover I52 and includes upper and lower tubular-shaped portions I88a and I801). A valve seat I82 is formed in lower portion I80b and contacts with ball I84 to form the check valve. To limit the upward movement of ball I84 during the exhaust or pumping stroke of pump 36, a flat wedge I86 is wedged into the cylindrically-shaped upper section I80a of the body of check valve I80. A conduit I88 (Figures 6. 3 and 9),whichfeeds water to the sealer blade assembly, is connected to the upper section I-a of the body of-valve I80. i l N Referring to Figures '1 and 8., it will beseen that cover 152 is raised around the well portion I68a of pump casing I68 to form a seat I90 for the rubber diaphragm I 92 of pump 36. The edge of diaphragm I92 is held in sealed relationship withseat I90 by means of a ring I'94 (Figures '1 and 8), which issecured to cover I52 by means of screws I96. This leaves thecenter section of,

mounted on a fulcrum stud, generally indicated at 206 (Figure 6). Fulcrum stud 206 is connected to an eccentric hex nut 90, which, as describedhereinabove, holds pulleys 84 and. 86 on and connects them to shaft 82. Hexnut 90 has a hole 20I extending into its forward end, the

axis of which is parallel'to but spaced from the axis of shaft 82. Fulcrum stud 266 includes. a hex-shaped portion 286a, a driving shaft 286b, the axis ofwhich is aligned with the axis of hexshaped portion 266a, .and an eccentric portion 2060, the axis of which is spaced from but parallel to the axis of hex-shaped portion 206a and shaft 20619. Eccentric portion 2060 fits eccentric hole 20I and is held in position therein by means:

of. a set screw 2I8. .Shaft 286?) extends through a hole 2I2 (Figurefi) in eccentric'bearing 204 and is .held in position therein by means of a springclip 2I4 (Figures 6 and 8). Shaft. I98 extends upwardly through bearing 284 transversely to the axis of shaft 20% and is connected thereto bynuts2I6 and2I8..

Thus it will be seen that the shaft 206!) of fulcrum stud 206, in effect, is a crank on shaft 82. Furthermore, by. adjusting fulcrum stud 206 with respect to eccentric bearing 80, the axis of shaft 20Gb may be moved toward or away from the axis of shaft 82, thus increasing or decreasing thelength of the stroke imparted by fulcrum stud 208 to shaft I98 (Figures 3 and 8) through eccentric bearing 204. Thus, the amount of water pumped by pump 36. may be readily controlled by making one simple adjustment.

Referringto Figures .19 and 20, as described hereinabove, the sealer blade assembly 40 is mounted on sealer table 42. The envelopes are fedacross sealer table 42 by conveyor belt 32 I (Figure. .3) and separator foot 48, and pressure feet 50; and 52 coact. with the split sealer table 42 (Figures 19 and 20) .to open the flap of each en-.

velope; so that it passes beneath portion42l of table 42 into contact with the blade of the sealer assembly 40, all. as willbe-fully described hereinafter. The sealer blade assembly includes a combination reservoir and sealer blade, generally indicated at 220 (Figures 21 and 24). The reservoir portion 22 0aof the combination sealer blade and reservoir includes four integral walls and a dividing partition 2201) (Figures 22 and 24) The sealer blade portion 2200 is V-shaped in cross section (Figure 23) and as it is followed rearwardly, it gradually tapers upwardly toward connected to an eccentric bearing 204, which is.

7 sealer. table 42 (Figure21); The upper'edge of sealer blade'portion 2200 has -a flange 220d (Figure 24) thereon, which, together withthe... top surface or the walls-of reservoir portion 229a,; are

' soldered to the undersurface of table 42. This closes the tops of both the sealer blade and reservoir portions of the combination sealer blade and-reservoir 220. The sealer blade is provided witlra' longitudinal slot 222 extending through its bottom' edge, through which water is supplied to=thegumn1ed surface of each envelope flap.

Dividing partition 22iI-b (Figure 24) divides-the reservoir into inlet and outlet sections 224 and 226 which are connect'ed by bypass passage'228. -Inlet and outlet sections-224 and 226 of reservoir 22211 are connected to the interior of sealer blade 2200 by inlet port 235' and outlet port 232, respectively.

The bottom of reservoir 2290, is closed by acap," enerally indicated at 234 (Figures 22 and 25). Cap 234 is connected to reservoir 220a by means of a pair of screws-233 and 24B.;(Figure 22) ,j'and'the joint between cap 234 and reservoir 220a issealed by a gasket 242. Cap 234 includes inlet: and outlet ducts 234a and 2342) (Figure 22),

whichextend upwardly into reservoir 228a and 7 open just beneath sealer table 42. Inlet duct 234ais connected to plastic conduit I83 (Figure 3) ,:and outlet duct 2341) is connected by a plastic conduit2'44 (Figures 3, 9 and 19) to a nipple 245 formed on cover I52 above the overflow section I48 of tank 33. Thus, water pumped'up through conduit I88 into the reservoir 2260. through inlet turn will take place. This ensuresthat the blade will always be amply supplied with water.

To guidethe'flaps of envelopes. beneath the sealer blade, to. hold the flaps into contact with the sealer blade, and to catch any drops of water that may drop iromslot 222 ('Figure21); a tension blade, generally'lindieated at 2461(Figures 19,20, 2l'and 25) is provided. The tension blade 24% includes'a flap-guiding portion 245a (Figure 19) slanting'downwardly to theright, as viewed in Figure 19; which guides the flaps of the envelopes upwardly toward the sealer blade. Portion 246a of tension blade 246 includes a'downwardlyextending flange 24.611 which is attached to cap 234 by screws 2.48 and 259 to mount tension blade 248 on'the sealer blade assembly. The tension bladeportion 2 360 is V-shaped in cross section and'coniorms to the shape of the sealer blade EZGcKFigures 21, 23 and that when thefiap of an envelope passes between thetension and'sealer blades, it is bent into a V shape,- while the body of the .flap bearing against the underside of table 42 will force the apex of this (Figure 23) into contact with the moistening slot 222 of the sealer blade 2200. Thus,- the tension blade ensures excellent contact between the gummed. surface of each flap and moistening slot 222, causing the'water-filled slot 222=to thoroughly moisten the gummed surface :of each envelope flap.

It will be noticed that the forward end of the tension blade portion 246a of tension blade 246 I; will be noticed has a. slob-25E) .(Fisure25) in its bottomlqThis is to direct any excess water dripping fromrthe slot 1-222 in sealer blade 2200 onto the. tension blade '24 3a into. an overflow cup 23.40 (Figure 21) Cup 25340 is formed as an. integral part of-.cap 234 and is connected by apassage 2521to=the over flow. .ducta234b. Thus..- any water .passin through slot 222 (Figure 24.) in thetensionblade and not: applied to an envelope flap drops. upon thetension blade and isdirectedinto cup 2340. The water flows from cup 2340 into overflow duct 23 1b, and thus it passes into the overflow section I 48 (Figure 8) of tank 38.

Thus, when the machine is to be .used, tank 38 is filled through opening I65 (Figure 9),.which isthenplugged by, plug i561 Next, the switch 254 (Figure l) 'controllingmotor 3'0 (Figure 3) is closed and motor 38' thendrives shaft 82 (Figure 6).- "Shaft 82 drives fulcrum studl2fl6. (FiguresB and 6) -,I which drives actuatingishaft E Eli-through eccentric bearing 204"with a. reciprocating'action;v As shaft I918 (Figures vSand. 10) moves upwardly, check valve I closes .and water is :forced past ball I12 into well 168a. On

the downward stroke of shaft; I98, ball. I12 closes,

intake-ductulfillb and air is. forced :pastcheck valve I80. As this pumping action continues, well I 68a, conduits I18 .and; I 88 and. the .sealer blade reservoir become filled with water. Then, during each downward stroke of shaft-1,98, the diaphragm pumps water through .port 2230.. into sealer blades22flc (Figure 24). The water which has circulated. throughthe blade passes out port 232-"andthence down through duct 23412 and conduit 244- the overflow section I 48: (Figure 8) oftank 38.

During operation of the machine, the water circulating through sealer blade 2260 (Figure 24) picks 'up-foreign material, such as 'the adhesive from the flaps of the envelopesbeing sealed, which enters the sealer blade through the slot 222- 'Ihecirculating :water carries this (foreign material back to; the. overflow section I48 (Figure 8) ofwtank 38, where it settles to the bottom. Screen I 42 filters the water as it passes-from the-overflow sectioninto the supply section, preventing recirculation of .the. foreign .material. This circulation of water through the sealer blade keeps the sealerc'bladenclean, so that :slot; 222 cannot become blocked .With adhesive material, and turthermorathe foreign material, .when removed-from thesealer blade, is segregated in tank 38,-so thatit cannot .be recirculated. .After a period of extendeduse, it is a simple matter to loosen wingnuts I562 and IE4. (Figure 3). and removerthe tank 38.,and screen E421;(Figure 8) for cleaning.

As zpointed. out; hereinabove,.:a separator foot is andtwo pressur'eieet 5lland52 (Figure 3) are provided to separate theflapfrom each. envelope as-it passes across the sealer table42 .and-to hold the envelope iii-contact, with the conveyor belt 32' sot-hat theiconveyor belt will feed theenvelopesi. pPteferring to-Figures 19 and 20, slot 54 v divides. the sealer tableinto'sections 42b and 420.

Section 420 islpositionedin a plane beneaththe plane of the mainportion of section 42b (Figure 19). "This permits separator foot 46 (Figure 3) to separate the envelopes as it presses downwardly upon conveyor belt 32. Separator foot 48 (Figure l7 )includes a pair of supporting bracketsZ-EE by means of which separator foot lBIis mounted on a stud shaft 258 (Figure 14) mounted on extending forwardly fromwall E4 (Figure 4); Separator foot 48 (Figure 2) is on stud'shaft 212 (Figure 14).

presses downwardly upon pressure foot 52. limit downwardly movement of foot-52, it is pro- 9 resiliently pressed downwardly by arm 26211 of a coil spring 262. The other end of spring 262 is connected to nut'264. Referring to Figures 12 and 17',"it will be noted that separator foot 48 has a cutout portion 48a, which. is semicircular in shape andis positioned directly above conveyor belt 32. Tolimit downward movement of separator foot 48, it is provided with an adjustable screw '266, which is mounted on a bracket 48b. The'lower-Uend of screw 266 (Figure 14) bears on a pin 268 mounted on Wall. Thus, byadj'usting the screw 266 (Figure-14), the position of separatorfoot 48 with respect to belt 32may be controlled; As the separator foot extends around belt 32, it efficiently separates the envelopes fed. by belt 32. i I

' Each envelope is maintained in contact with belt 32 and its flapopened by pressure foot 50. Pressure foot 50 includes a hub portion 56aw(Figure 16) which pivotally mounts'pressure foot 56 1Stud shaft 212 includes a portion 2121;. of reduced diameter, which extends through wall 64 (Figure 2) and is connected to wall 64 by nut.266. A coil spring 214 (Figure 2) is mounted on theouter end of shaft 212, has one end secured to nut 216, and the other end 214a (Figure 11) presses foot 56 downwardly toward belt 32. The lowerend of this foot is curved to fit the shape of belt 32 (Figures 12 and 16), and thus this foot, in addition to holding the envelope in contact with the conveyor belt, also separates the flap from the body of .each envelope. To limit downward movement of pressure foot 50, it is provided with an adjustable screw 296, which is mounted on foot 56 in a threaded'hole and has its lower end in engagement with the portion of separator foot 48.- Thus, by adjusting screw 296 (Figure 11), the relationship betweenfoot 56 and conveyor belt 32 is controlled.

Pressure foot 52 (Figures 2, ll, 14 and 18) includes a hub portion 52a, by means of which foot 52 is pivotally mounted on stud shaft 218 (Figures 2 and 14). Stud shaft 218 (Figure 2) includes a portion of reduced diameter 2180. (Figure 2), which extends through a hole in wall 64. The shaft 218 is secured to wall 64 by means of nut 286. Pressure foot 52 is pressed downwardly toward conveyor belt 32 by means of a coil spring 282 mounted on the forward end of stud shaft 218. One end of coil spring 282 is connected to nut 284, and the other end 282a (Figure 11) vided with an adjustable screw 286, which is mounted in a threaded hole in a lug 521) (Figure 14) formed on the hub 52a of foot 52. The lower end of screw 286 engages a pin 288 on wall 64, and thus by adjusting screw 286 upwardly and downwardly, the relationship of foot 52 with respect to belt 32 may be adjusted.

It will be noted that pressure foot 52 includes aifoot portion 520 (Figure 11) of substantial length. This foot portion has a lower surface 292 (Figurew13) which coacts with belt 32 to maintain the fiap 216a separated from each en velope 216. At this time, the flap 216a passes beneath portion 42b (Figures 19 and 20) of sealer table 42, and then it is guided by the undersurface of the sealer table 42 and the guiding portion 246a (Figure 19) of tension blade 246 to the sealer blade 2260 (Figure 21). As pointed out hereinabove, as the flap of each envelope passes sealer blade 226e, tension blade 246 places the flap under tension, insuring contact between its gummed surface and th- "hastening slot in the sealer blade.

In order to separate the flaps of light envelopes, a pressure foot 294 (Figures 2 and 11) is provided. This pressure foot is, in reality, one end of a coil spring 294a, the coil of which is mounted on a stud shaft 296, which is secured to wall 64. The other end of coil spring 294a is connected to nut 298. The endof pressure foot 294 bears downwardly upon envelopes just before they pass beneath section 42b of the sealer table. As this pressure is applied rearwardly of belt 32 (Figure 13), it coacts with the leading edge of portion 42b of plate 42 to separate the flap from the body of each light envelope. Once the lead ing edge of an envelope is positioned beneath section 422) of sealer table 42, section 422) is positioned between the flap and the envelope, the flap then being fed into contact with the sealer blade. Thus, pressure feet 56, 52 and 294 (Figures 2 and .11) coact with the sealer table 42 to separate the flap from envelopes passing through the machine, so that they will pass beneath portion 421) of plate 42 and across the sealer blade. After they have passed the sealer blade, their leading edges are gripped between feed roller 34 and the pressure roller 56 and fed from the machine. 1

i The pressure feet and feedroller are covered by a housing, generally indicated at 366 (Figures 1 and 11). This housing is pivotally mounted on a shaft 362, which is mounted on the framework of the machine. When housing 366 is raised,-it pivots about shaft 362, exposing the pressure feet and the feed roller. When it is in a lowered position, its downward movement is limited by alimit stop 364 (Figures 3 and 11), and it is held in this position by a spring 366, which snaps beneath limit stop 364.

The envelopes to be sealed are positioned above plate 44, and their flaps positioned downwardly. The forward edges of the envelopes abut against wall 366a (Figures 1 and 3) of housing 360, and they are supported at an angle by means of a guide 46 (Figures 1 and 2). Guide 46 includes a supporting member 308, which extends through a bracket 3l6 on the underside of table 44 (Figure 3) Thus, guide 46 may be adjusted longitudinally with respect to table 44 to accommodate envelopes of different sizes. When the hopper has been filled with envelopes, they are pressed rearwardly so that theirrear edges are positioned adjacent plate 14 (Figure 1). Then the undersurface of the lowermost envelope is engaged by the exposed portion of conveyor belt 32 (Figure 1), and fed through the machine. The envelopes are fed singly by conveyor belt 32, separator foot 48 (Figure 11) insuring that only one envelope will pass through the machine at a time.

It may thus be seen that by virtue-of the inclination of hopper table 44 downwardly (see Figure 1) with respect to the direction of travel of the envelopes that there is a natural tendency for the envelopes to feed toward the conveyor belt. Also because of the upward inclination of portion 42b of table 42, the envelope as it feed along tends to bridge the hollow between the two tables, 1. e. the body of the envelope tends to bridge this hollow, while the flap, being separated by the buckling action (see Figs. 12 and 13) of belt 32 and the pressure feet, travels along table portion 420 (see Fig. 3) which underlies table portion 422). Hence it follows that the inclined tables, the pressure feet Hand 52, belt 32 and table portion 420 coact in a highly efiicient manner to ef- Thus, .a ractical andefilci'ent seaiin machine has-been disclosed, in whichtthe sealer blade is constantly supplied with water and in which the sealer blade is cleanedby the: water circulating through it. Furthermore, in this construction, the pressure feet are designed so that. a: large number" of different sizes and thicknesses of, en-

velopes may be sealed without requiring adjustments. If adjustments are. required. in separator foot 48 or pressure feetlfili and 52', these adjustmerits may be easily made by raising cover 368 and adjusting screws 266; 2B6 and 290. The machine has a-positive feed for'feeding envelopes from the machine, which is also designed to officiently seal each envelope as it leaves the machine. Furt'hermorathe machine is also so. constructed that itmaybe manually operated: by means of a, crank .It will thus be seen that the several objects hereinabove mentionedas well as many others, are successfully accomplished.

As many possible embodiments may be made of the above invention and as many changes might'be made in the embodiment above set forth, all without departing from the scope of the invention, it is to be understood that all matter hereinabove setforth or shown in the accomanyin drawings isto be interpreted as illustrative and not in a limiting sense. I

lclaim:

1. In a letter scaling machine, in combination, a sealer table, means forming a slit in saidtable to divide said table into two sections, a sealer blade mounted beneath one of said sections, a conveyor belt circular in cross section for conveying envelopes'across said sealer table, means to drive said conveyor belt, a pressure foot, and means to resiliently urge said ressure foot toward said belt, the face of said pressure foot juxtaposed to said belt being curved to fit said belt, the'face of said foot and said belt acting on each envelope fed through said machine to separate the flap from the envelope so that the flap passes through the slit in said sealer table and thence into contact with said sealer blade to moisten the gummed flap.

2. In a letter sealing machine, in combination,

a sealer table, a sealer blade positioned beneath said sealer table and having a moistening slot therein, means to supply water to said sealer blade, a conveyor belt for feeding envelopes across said sealer table, said conveyor belt being circular'in cross section, a pressure foot, means resilicntly urging said pressure foot towards said belt, said pressure foot having acurved' lower end, said pressure foot end coacting with said belt to separate the flaps from each envelope passing therebetween and also acting to hold said envelope in engagement withsaid conveyor belt to insure proper conveyance thereof by the conveyor belt, and a second pressure foot, said second pressure foot having a foot portion of substantial length juxtaposed to said belt, the acting surface of said foot portion being curved to fit said belt, said second foot maintaining said flap separated from said envelope so that it passes beneath said sealer table into contact with said sealer blade.

3. In a letter sealing machine, the combination of a table to support the body of an envelope during the sealing operation, means forming a hopper at the receiving end of said table to receive a stack of envelopes with their flaps in closed position, a conveyor element-movably associated with said tablefor successively. conveyingyenvelopeslthereoverfrom said hopper, a, movable member overlying. said conveyor element; said member and said element being positioned-adjacent that. portion' of said table along whichv the flap edge of, the envelope travels and positioned to engage the opposite sides. of said; envelope along its flap edge, .said-elementand saidrmember being configured to buckle thezenvelope adjacent its flap edge and thereby cause therenvclope flap to separate from the envelope body,;;and means to receive and moisten the'separatedtenveclope flaps as the envelope travels over said'table.

4. A machine in accordance with. 'c-laim...3, wherein the last-mentioned means includes a-portion of the table which. is bent downwardly from the: general plane thereof-and along which, the separated envelope flap slides; n5. A machine in accordance with claim;.3, wherein the last-mentioned'means includes azportion of the table'which'isibent downwardly from the general plane thereof and along whichthe separated envelope. flap slides, said last'ementioned means also including an upwardly inclined flap guiding memberwhich receives theflap from said table portion and guides it to the: moistening means. 7

6. A machine in accordance with :claim L3, wherein said last-mentioned means underlies'said table.

7. In a letter sealing machine, in combination, an envelope supporting table comprising downwardly and upwardly inclined portions, said \inclinations being in respect to theLd-ire'ction. of travel of an envelope: through the 6 machine, means to convey an envelope over said table, downwardly biased pressure-means overlying said conveying means to force thereagainst portions of the envelope adjacent its flapedge, said pressure means being located betweenthe ends of saidtable and accordingly in the hollow thereof, thereby to eiiect a downward-separation of the flap from the body of the envelope, the upwardly inclined portion of said table including a section lying in a'generally horizontal plane to receive the downwardlydefiected flap, and means underlying the upwardly inclined portion'of said table to receive and moisten the flap as the envelope travels over said last-mentioned table portion.

8. A 'machine in accordance with claim-'3, wherein the conveyor element includes a belt, the upper surface of which is convex and wherein-the movable member which overlies the conveyor belt includes a lower convex-surface so that when an envelope is gripped between said surfaces it buckles the envelope portion adjacent the flap edge thereof causing the flap to be deflected downwardly and accordingly separated from the body of the envelope;

9. In a letter sealing machine, in combination, a sealer device including a'sealer blade having an elongated wall portion in which is formed a long narrow moistening slot, and a reservoir'having a passage in fluid communication with the sealer blade so as to supplywater to themoistening slot, water inlet means and water outlet means associated with said reservoir, said outlet means having a flow capacityat least equal to the flow capacity of the inlet means-and so positioned as to maintain the level of the water in the reservoir above the bottom of the passage to the sealer blade, means to convey envelopes past said slot to moisten the gummed portions of the flaps thereof,- a' water tank, a supply conduit connecting said tank with said inlet passage, an exhaust conduit connecting said tank with said outlet passage, a pump associated with said supply passage to pump water therethrough to said reservoir, and a motor for driving said pump whereby water is pumped to said reservoir, circulated therethrough and exhausted therefrom to thereby effect a constant supply of circulating water to said slot.

10. In a letter sealing machine, in combination, a sealer device including a sealer blade having an elongated wall portion in which is formed a long narrow moistening slot, and a reservoir having a passage in fluid communication with the sealer blade so as to supply water to the moistening slot, water inlet means and water outlet means associated with said reservoir, said outlet means having a flow capacity at least equal to the flow capacity of the inlet means and so positioned as to maintain the level of the Water in the reservoir above the bottom of the passage to the sealer blade, means to convey envelopes past said slot to moisten the gummed portions of the flaps thereof, a water tank, a supply conduit connecting said tank with said inlet passage, an exhaust conduit connecting said tank with said outlet passage, a pump associated with said supply passage to pump water therethrough to said reservoir, a motor for driving said pump whereby water is pumped to said reservoir, circulated therethrough and exhausted therefrom to thereby eifect a constant supply of circulating water to said slot, and a screen in said tank separating said supply and exhaust conduits.

11. In a letter sealing machine, in combination, a sealer device including a sealer blade having an elongated wall portion in which is formed a long narrow moistening slot, and a reservoir having a passage in fluid communication with the sealer blade so as to supply water to the moistening slot, water inlet means and water outlet means associated with said reservoir, said outlet means having a, flow capacity at least equal to the flow capacity of the inlet means and so positioned as to maintain the level of the water in the reservoir above the bottom of the passage to the sealer blade, means to convey envelopes past said slot to moisten the gummed portions of the flaps thereof, a water tank, a supply conduit connecting said tank with said inlet passage, an exhaust conduit connecting said tank with said outlet passage, a pump associated with said supply passage to pump water therethrough to said reservoir, a motor for driving said pump whereby water is pumped to said reservoir, circulated therethrough and exhausted therefrom to thereby effect a constant supply of circulating water to said slot, and an overflow cup underlying at least a, portion of said slot and communicating with said exhaust conduit.

WILLIAM H. UHL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

